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jdraughn
11-24-2008, 10:47 PM
I am pretty new to high performance engines. I have helped my dad put take engines out, rebuild them, and put them back into a variety of cars (he is a mechanic by trade), but I don't really have a whole lot of knowledge, which I am hoping to change. I am 30 now by the way, just so you know your not talking to a 16 year old.

I was looking at getting a after-market block for my 1990 Corvette, and have been doing research about what kind of modifications are required to fit a engine into my car that has larger cubic inches. As I look at the small blocks and big blocks that Dart makes, the website has a few different options to choose from, like Cylinder Bore, Caps, Deck, ect.. How do I figure what cubic inches the engine will be from those specs? I always thought it was stroke * bore, but I don't know how to go from deck to stroke (if that is what I need to do).

I am thinking of going all out with the credit card and putting in a 500CI+ monster with turbos. I figure I am going to start with reading tons of books, articles and anything else I can find out about the theory behind building Torque and HP for the next few months. I will ask a lot of questions as I try to learn everything I can, and also read up on fabricating custom parts.

I don't want to modify the frame, but I think I would be comfortable with the welding, cutting and bending required for any custom brackets or exhaust work that needs to be done, and I look forward to figuring out how to build my own turbo system.

I was also planning on basically getting rid of all the electrical in the entire car and rebuilding it from scratch with LCD touch screens to display and allow input for controlling anything in the car that uses electricity. I am talking gauges for temp, pressure and speeds, and operation of the windows, stereo system, HVAC, GPS and Cullular, ect... The car is going to be so heavily customized that it will only look like a Corvette from the outside, and the inside will hopefully be one of the most futuristic looking cars.

I will want to get a generic fuel injection setup for my new engine where I can view and modify the parameters, preferably in real time by interfacing with a PC.

I know programming and I am starting to learn how to program micro-controllers which is how I plan on redoing all the electrical in my entire car.

At this point I am trying to figure out what will fit in my car, with what modifications, and how much HP and Torque I could create with a good basic performance setup and Turbos with the different size engines.

I want this to be able to be driven daily, and from what I have basically gotten the jest of, is that as you start adding hotter cams, and as engines have a higher RPM curve, it starts to turn more into a "race car". I am looking more for tons of low end torque. As far as racing is concerned, the quarter mile is probably all I would ever probably mess around with at the local track.

lun40119
11-24-2008, 11:45 PM
Bore*Bore*stroke*.7854*number of cylinders

Hope this helps..........

Sounds like you are going to build a monster.......Good Luck

want-a-be
11-25-2008, 03:13 AM
A formula you can use to figure Cubic inches is.... bore x bore x stroke x .7854 x the number of cylinders = cubic inches. So if you have a block that has a 4.125" bore and a 3.750" stroke with 8 cylinders it would figure like this. 4.125" x 4.125" x 3.750" x .7854 x 8 = 400.9 cubic inches. Rod length, and deck height have nothing to do with the equation.

Feel free to ask all you need to know. We will be more then happy to help out. I'd be glad to help if I can. PM me if you need help outside the forum. But you'll get some good help by posting questions here.

Don

Awesome Bill
11-27-2008, 11:42 AM
We specialize in the large SBC, & LS engines along with the SBF up to 500" with a 9.5" block. As of date, we can make over 1100 real hp with the SBX spalyed valve stuff. We've done it more than once. With a turbo, the sky is the limit. Whether you use real pump gas or race gas is your only limit. With pump gas and an intercooler or alky, you could make 1500 hp with no problems with the turbo. Pump gas is kinda tricky and will detonate over 11-1 compression. So the cold air or alky will help. We have installed alky injection units over the gas and done very well. Under wot conditions, we have a 180lb injection laying a large amount of alky over the gas and it brings the detonation factor to 0. You can run as much as 12.5-1 with real pump gas and a turbo or pro charger. So if your really interested in a 500" 4.38/4.4 b/s sbc or ford, let me know. They are becoming a normal for us.

Trmnatr
12-01-2008, 01:43 PM
Bore*Bore*stroke*.7854*number of cylinders

Hope this helps..........

Sounds like you are going to build a monster.......Good Luck


I use,,,,

bore x bore x stroke x 3.14 = B / 4 = B * 8 = CID

want-a-be
12-02-2008, 01:47 AM
The .7854 pretty much condenses the, ( x 3.14 = B / 4 = B ), part of the equation. I'm no mathematician,...but the engine builder who taught me the .7854 part of the equation I use is.

Don

CWA1976
12-02-2008, 05:46 AM
No matter what formula you use, for the volume of a cylinder, the result is the same.

1. 3.1416 X radius squared X depth = volume of one cylinder

2. 3.1416 X bore squared X depth, divided by 4 = volume of one cylinder

3. .7854 X bore squared X depth = volume of one cylinder

the .7854 is the result when 3.1416 is divided by 4

vince

rbrduck71
12-28-2008, 05:59 PM
ITS VERY CONFUSING, AS MUCH AS I WANNA KNOW DISPLACEMENT, I ALSO WANNA KNOW COMPRESSION RATIO, NOT JUST ANOTHER BUILDERS ASS UMPTION, HEADS, DART SAYS 49cc, GASKETS FELPRO SAYS .041in WHATS THAT IN cc, WHAT DO I MEASURE ON STOCK PISTONS? WHATS MATH FORMULA? CAN A GUY WITHOUT COLLEGE DEGREE FIGURE OUT COMPRESSION RATIO AND DISPLACEMENT? AND WHY DID I GROW UP IN A FARM TOWN WITH NO PERFORMANCE SHOPS OR KNOWLEDGE? SORRY JUST WHINING!
RUBBERDUCK

rbrduck71
12-28-2008, 06:00 PM
What Is To Be Gained Going From .041 To A .015 Gasket?
Duck

lun40119
12-28-2008, 07:44 PM
Depending on the quench now...........you could pile drive the piston into the head..........google compression ratio calculator, and plug the numbers in.

want-a-be
12-28-2008, 09:22 PM
Depending on the quench now...........you could pile drive the piston into the head..........google compression ratio calculator, and plug the numbers in.

Not to mention you might get into some valves. But if everything were to clear it would raise your compression.

Don

rbrduck71
12-30-2008, 02:31 PM
You Guys Missed Part Of My Question, Piston Dome Volumne? How Do I Do That? Piston Deck Clearance, From Where To Where Do I Measure? Thanks Again
Duck

want-a-be
12-30-2008, 04:14 PM
I do the rock method. Check with a dial indicator. Bring the piston up to TDC. Rock the piston up then down and take the average. Do this on both sides of the pistons, and on all 4 corners.

Don

rbrduck71
12-30-2008, 06:36 PM
that takes care of piston deck clearance right? top o piston to deck? now what about piston dome volumne? sorry about the IGNORANCE just wanna get it right while motors apart. i will have my dart heads apart this week so we can finish that conversation about the iron eagle 180/49cc guide leak problem, i live in a one stoplight town so this websites all i got! THANKS AGAIN!
rubberduck

want-a-be
12-30-2008, 07:37 PM
Thats measured on the deack part of the piston...not the dome. Sorry for stating the obvious but just wanted to make sure. How much dome do you have?

Where are you from.,..just the state is fine.

Don

rbrduck71
12-31-2008, 02:13 AM
Central San Joaquin Valley, California

rbrduck71
01-02-2009, 02:31 PM
that would be the 200 and something mile by 100 and something mile chunk in the middle of california